This invention relates to interlocking building blocks or bricks which can be used to construct a wall without the need for mortar between the bricks.
Most brick or cement walls are constructed with a layer of mortar located between adjacent blocks and between adjacent layers of blocks. The mortar layer serves three primary purposes: one, it provides a mortar bed of various thickness in order to vertically align the bricks; two, it seals the interstices; and three, it strengthens the connection between the blocks.
However, systems are known which employ interlocking "mortarless" blocks which can be placed directly adjacent each other and directly on top of each other. Since no mortar is placed between the bricks, the blocks must be designed to interlock so as to maximize the stability of the wall as a whole. Furthermore, the interconnection between the blocks must be such that it ensures vertical alignment of the blocks. In such systems, mortar or grout is normally poured between the blocks after the wall is constructed.
Examples of known mortarless brick systems are shown in U.S. Pat. No. 3,534,518 to Zagray and U.S. Pat. No. 1,686,270 to Dwyer. However, these brick systems suffer from various drawbacks. One, they are generally complex in design, and thus are both difficult and expensive to manufacture and difficult to assemble properly. Second, they do not necessarily interconnect in a stable manner which minimizes possible misalignment in the direction transverse to the wall. Third, they often require several different types of blocks to construct a wall, and thus are difficult to store. Primarily due to the complexity and inefficiency of the prior systems, they have not had great commercial success.